<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>
	<body>
	</body>
	<script type="text/javascript">
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		console.log(obj.a);
		
		
		obj.a=6;
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		Object.defineProperty(obj,"a",{
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			emumerable:true
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		console.log(obj.a);
		
		
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</html>
